morula

noun

mor·​u·​la ˈmȯr-(y)ə-lə 

ˈmär-

plural morulae ˈmȯr-(y)ə-ˌlē 

-ˌlī, 

ˈmär-

also morulas

: a globular solid mass of blastomeres formed by cleavage of a zygote that typically precedes the blastula

morular

ˈmȯr-(y)ə-lər 

ˈmär-

adjective

morulation

ˌmȯr-(y)ə-ˈlā-shən 

ˌmär-

noun

Word History

Etymology

borrowed from New Latin (in a German context), from Latin mōrum "black mulberry, blackberry" + New Latin -ula (as in gastrula, planula) — more at mulberry

Note: The term was introduced by the German biologist Ernst Haeckel (1834-1919) in Die Kalkschwämme, Band 1 (Berlin, 1872), p. 112: "Der Organismus der Kalkschwämme bildet zunächst, nachdem er den monoplastiden Zustand der Eizelle durch die Befruchtung der letzeren überwunden und sich durch die vollbrachte 'Furchtung' des Eies von der ersten zur zweiten Individualitäts-Ordnung erhoben hat, die sogenannte 'Maulbeer-Form' oder 'Brombeer-Form,' welche wir ein für allemal als Morula bezeichnen wollen." ("After the calcareous-sponge organism goes beyond the undifferentiated condition of the egg cell through fertilization, and through completed 'cleavage' of the egg has risen from the first to the second rank of individuality, it forms at first the so-called 'mulberry-form' or 'blackberry-form,' which we will designate once and for all as the morula.")

First Known Use

1875, in the meaning defined above

Medical Definition

morula

noun

mor·​u·​la ˈmȯr-(y)ə-lə, ˈmär- 

plural morulae -ˌlē, -ˌlī 

: a globular solid mass of blastomeres formed by cleavage of a zygote that typically precedes the blastula compare gastrula

morular

-lər 

adjective

morulation

ˌmȯr-(y)ə-ˈlā-shən, ˌmär- 

noun